= Radioactive Specimen
Elsmore, New South Wales, Australia
Several extremely lustrous, dark brown, twinned Cassiterite crystals are intergrown, clustered near the top of the matrix. The largest crystal measures 5/8" wide X 3/8" thick. Dana locale.
Size: 1 1/4" tall, 1 1/8" wide, 3/4" thick.
Order item MI-058 SOLD
Wolfram Camp Mine, Queensland, Australia (Dana locale)
These excellent examples of native Bismuth are from a deposit in Queensland where rich masses of metallic silvery-gray native Bismuth were formed in open voids, within a large body of crystallized Quartz. Most of the specimens have very obvious, large flat faces which are the impressions of large, prismatic Quartz crystal faces, i.e., the native Bismuth was deposited after the Quartz, in large open voids between the Quartz crystals. Other specimens, like items D. and F., have parallel grooves -- these are possibly the negative impressions (casts) of the stepped faces on large Quartz crystals. Items D. and E. have the negative impressions of Quartz crystal terminations in the Bismuth. This is very obvious in the photo of item E. -- the impression of a smaller Quartz crystal termination is present on the back of the specimen, on item D., as oriented in the photo. Some specimens have minor amounts of crystalline/massive brown Wolframite associated, and/or small amounts of massive white Quartz. Metallic lead-gray massive Molybdenite richly coats one of the flat surfaces of the specimen, on item C. Item A. exhibits the bright, metallic silvery natural cleavage of the native Bismuth on the front of the specimen, as shown in the accompanying photo, while the sides and back of the specimen are in natural condition, as collected. On all other specimens, the natural form of the specimen is the shape of the cast of the Quartz or Wolframite, with very little or no cleavage faces present. The gram weights are given below, as an additional size measurement, for your information. 448.00 grams = 1 pound . . . . item G. weighs approx. 1 pound, and item H. weighs approx. 1 1/4 pound! Order item MI-059, A. through H.
Huanzala Mine, Huanuco, Ancash Province, Peru
This locality for Pyrite (and the crystal forms encountered at the Huanzala Mine) is described in the "Mineralogical Record" magazine, Vol. 28, No. 4, July-Aug. 1997 (special issue on Peruvian mineral localities), P. 53. This unusual stalactitic form is not mentioned by the authors of the article. The specimens offered here are stalactitic in form, i.e., each specimen has a finger-like central core composed of massive Pyrite, upon which many individual, bright brassy metallic dodecahedral Pyrite crystals were formed. The crystals range in size from 1/8", up to 1/2" across on item A., D., and E., and up to 5/8" across on items B. and C. None of the specimens have rock matrix.
Sizes and prices are as follows. The sizes are given as length and diameter, in inches.
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